linux/drivers/ata/pata_falcon.c
Michael Schmitz 8847d42d7a ata: pata_falcon: add data_swab option to byte-swap disk data
Some users of pata_falcon on Q40 have IDE disks in default
IDE little endian byte order, whereas legacy disks use
host-native big-endian byte order as on the Atari Falcon.

Add module parameter 'data_swab' to allow connecting drives
with non-native data byte order. Drives selected by the
data_swap bit mask will have their user data byte-swapped to
host byte order, i.e. 'pata_falcon.data_swab=2' will byte-swap
all user data on drive B, leaving data on drive A in native
byte order. On Q40, drives on a second IDE interface may be
added to the bit mask as bits 2 and 3.

Default setting is no byte swapping, i.e. compatibility with
the native Falcon or Q40 operating system disk format.

Cc: William R Sowerbutts <will@sowerbutts.com>
Cc: Finn Thain <fthain@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: William R Sowerbutts <will@sowerbutts.com>
Signed-off-by: Michael Schmitz <schmitzmic@gmail.com>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
2023-08-28 19:14:41 +09:00

242 lines
6.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Atari Falcon PATA controller driver
*
* Copyright (c) 2016 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
* Based on falconide.c:
*
* Created 12 Jul 1997 by Geert Uytterhoeven
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_cmnd.h>
#include <linux/ata.h>
#include <linux/libata.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <asm/setup.h>
#include <asm/atarihw.h>
#include <asm/atariints.h>
#include <asm/atari_stdma.h>
#define DRV_NAME "pata_falcon"
#define DRV_VERSION "0.1.0"
static int pata_falcon_swap_mask;
module_param_named(data_swab, pata_falcon_swap_mask, int, 0444);
MODULE_PARM_DESC(data_swab, "Data byte swap enable/disable bitmap (0x1==drive1, 0x2==drive2, 0x4==drive3, 0x8==drive4, default==0)");
static const struct scsi_host_template pata_falcon_sht = {
ATA_PIO_SHT(DRV_NAME),
};
static unsigned int pata_falcon_data_xfer(struct ata_queued_cmd *qc,
unsigned char *buf,
unsigned int buflen, int rw)
{
struct ata_device *dev = qc->dev;
struct ata_port *ap = dev->link->ap;
void __iomem *data_addr = ap->ioaddr.data_addr;
unsigned int words = buflen >> 1;
struct scsi_cmnd *cmd = qc->scsicmd;
bool swap = 1;
if (dev->class == ATA_DEV_ATA && cmd &&
!blk_rq_is_passthrough(scsi_cmd_to_rq(cmd)))
swap = (uintptr_t)ap->private_data & BIT(dev->devno);
/* Transfer multiple of 2 bytes */
if (rw == READ) {
if (swap)
raw_insw_swapw(data_addr, (u16 *)buf, words);
else
raw_insw(data_addr, (u16 *)buf, words);
} else {
if (swap)
raw_outsw_swapw(data_addr, (u16 *)buf, words);
else
raw_outsw(data_addr, (u16 *)buf, words);
}
/* Transfer trailing byte, if any. */
if (unlikely(buflen & 0x01)) {
unsigned char pad[2] = { };
/* Point buf to the tail of buffer */
buf += buflen - 1;
if (rw == READ) {
if (swap)
raw_insw_swapw(data_addr, (u16 *)pad, 1);
else
raw_insw(data_addr, (u16 *)pad, 1);
*buf = pad[0];
} else {
pad[0] = *buf;
if (swap)
raw_outsw_swapw(data_addr, (u16 *)pad, 1);
else
raw_outsw(data_addr, (u16 *)pad, 1);
}
words++;
}
return words << 1;
}
/*
* Provide our own set_mode() as we don't want to change anything that has
* already been configured..
*/
static int pata_falcon_set_mode(struct ata_link *link,
struct ata_device **unused)
{
struct ata_device *dev;
ata_for_each_dev(dev, link, ENABLED) {
/* We don't really care */
dev->pio_mode = dev->xfer_mode = XFER_PIO_0;
dev->xfer_shift = ATA_SHIFT_PIO;
dev->flags |= ATA_DFLAG_PIO;
ata_dev_info(dev, "configured for PIO\n");
}
return 0;
}
static struct ata_port_operations pata_falcon_ops = {
.inherits = &ata_sff_port_ops,
.sff_data_xfer = pata_falcon_data_xfer,
.cable_detect = ata_cable_unknown,
.set_mode = pata_falcon_set_mode,
};
static int __init pata_falcon_init_one(struct platform_device *pdev)
{
struct resource *base_mem_res, *ctl_mem_res;
struct resource *base_res, *ctl_res, *irq_res;
struct ata_host *host;
struct ata_port *ap;
void __iomem *base, *ctl_base;
int mask_shift = 0; /* Q40 & Falcon default */
int irq = 0, io_offset = 1, reg_shift = 2; /* Falcon defaults */
dev_info(&pdev->dev, "Atari Falcon and Q40/Q60 PATA controller\n");
base_res = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (base_res && !devm_request_region(&pdev->dev, base_res->start,
resource_size(base_res), DRV_NAME)) {
dev_err(&pdev->dev, "resources busy\n");
return -EBUSY;
}
ctl_res = platform_get_resource(pdev, IORESOURCE_IO, 1);
if (ctl_res && !devm_request_region(&pdev->dev, ctl_res->start,
resource_size(ctl_res), DRV_NAME)) {
dev_err(&pdev->dev, "resources busy\n");
return -EBUSY;
}
base_mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!base_mem_res)
return -ENODEV;
if (!devm_request_mem_region(&pdev->dev, base_mem_res->start,
resource_size(base_mem_res), DRV_NAME)) {
dev_err(&pdev->dev, "resources busy\n");
return -EBUSY;
}
ctl_mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (!ctl_mem_res)
return -ENODEV;
/* allocate host */
host = ata_host_alloc(&pdev->dev, 1);
if (!host)
return -ENOMEM;
ap = host->ports[0];
ap->ops = &pata_falcon_ops;
ap->pio_mask = ATA_PIO4;
ap->flags |= ATA_FLAG_SLAVE_POSS | ATA_FLAG_NO_IORDY;
/* N.B. this assumes data_addr will be used for word-sized I/O only */
ap->ioaddr.data_addr = (void __iomem *)base_mem_res->start;
if (base_res) { /* only Q40 has IO resources */
io_offset = 0x10000;
reg_shift = 0;
base = (void __iomem *)base_res->start;
ctl_base = (void __iomem *)ctl_res->start;
} else {
base = (void __iomem *)base_mem_res->start;
ctl_base = (void __iomem *)ctl_mem_res->start;
}
ap->ioaddr.error_addr = base + io_offset + (1 << reg_shift);
ap->ioaddr.feature_addr = base + io_offset + (1 << reg_shift);
ap->ioaddr.nsect_addr = base + io_offset + (2 << reg_shift);
ap->ioaddr.lbal_addr = base + io_offset + (3 << reg_shift);
ap->ioaddr.lbam_addr = base + io_offset + (4 << reg_shift);
ap->ioaddr.lbah_addr = base + io_offset + (5 << reg_shift);
ap->ioaddr.device_addr = base + io_offset + (6 << reg_shift);
ap->ioaddr.status_addr = base + io_offset + (7 << reg_shift);
ap->ioaddr.command_addr = base + io_offset + (7 << reg_shift);
ap->ioaddr.altstatus_addr = ctl_base + io_offset;
ap->ioaddr.ctl_addr = ctl_base + io_offset;
ata_port_desc(ap, "cmd %px ctl %px data %px",
base, ctl_base, ap->ioaddr.data_addr);
if (pdev->id > 0)
mask_shift = 2;
ap->private_data = (void *)(uintptr_t)(pata_falcon_swap_mask >> mask_shift);
irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (irq_res && irq_res->start > 0) {
irq = irq_res->start;
} else {
ap->flags |= ATA_FLAG_PIO_POLLING;
ata_port_desc(ap, "no IRQ, using PIO polling");
}
/* activate */
return ata_host_activate(host, irq, irq ? ata_sff_interrupt : NULL,
IRQF_SHARED, &pata_falcon_sht);
}
static int __exit pata_falcon_remove_one(struct platform_device *pdev)
{
struct ata_host *host = platform_get_drvdata(pdev);
ata_host_detach(host);
return 0;
}
static struct platform_driver pata_falcon_driver = {
.remove = __exit_p(pata_falcon_remove_one),
.driver = {
.name = "atari-falcon-ide",
},
};
module_platform_driver_probe(pata_falcon_driver, pata_falcon_init_one);
MODULE_AUTHOR("Bartlomiej Zolnierkiewicz");
MODULE_DESCRIPTION("low-level driver for Atari Falcon PATA");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:atari-falcon-ide");
MODULE_VERSION(DRV_VERSION);